Two Earth-sized planets could be hiding in the chilly margins of our Solar System, just beyond Neptune and Pluto. We just have to find them first.

BEC CREW 20 JAN 2015

Hints of two more planets lurking undetected way out near the edge of our Solar System have been found thanks to a new analysis of the belt of objects called the 'extreme trans-Neptunion objects’ (ETNO).

A team of astronomers from the Complutense University of Madrid in Spain and the University of Cambridge in the UK studied the orbits of 13 such ETNOs, including the dwarf planet Sedna, and found that they weren’t moving as expected. Something appears to be altering their orbits, the team reports, and that ‘something’ could be a couple of hidden planets at least the size of Earth, if not bigger.

"This excess of objects with unexpected orbital parameters makes us believe that some invisible forces are altering the distribution of the orbital elements of the ETNO, and we consider that the most probable explanation is that other unknown planets exist beyond Neptune and Pluto,” lead scientist, Carlos de la Fuente Marcos from the Complutense University of Madrid, told the Spanish Scientific News Service. “The exact number is uncertain, given that the data that we have is limited, but our calculations suggest that there are at least two planets, and probably more, within the confines of our Solar System."

Publishing their findings in two articles in the Monthly Notices of the Royal Astronomical Society Letters - available here and here - the researchers have estimated that if these planets exist, they would be located 200 astronomical units away from Earth, which is 200 times the distance between Earth and the Sun (one astronomical unit is the distance between the two).

The prospect of two more planets in our Solar System is pretty exciting, but there are problems with the proposal. Firstly, the team noted that the existence of these planets contrdicts current models on the formation of the Solar System, which only works if there are no planets moving in circular orbits further away from the Sun than Neptune, the Spanish Scientific News Service reports.

But a recent discovery supports the possibility that planets could actually form at great distances from their star. Late last year, scientists using the new Atacama Large Millimetre Array (ALMA) of telescopes in Chile found a planet-forming disk more than 100 astronomical units from a star called HL Tauri. This star is younger than our Sun, but more massive, and the confirmed presence of a planet-forming disc some 100 astronomical units away from it makes a case for the possibility that planets could also form as far 200 astronomical units away from their star.

That said, de la Fuente Marco and his team have got their work cut out for them in proving that these two planets actually exist. They’re too far away to ‘see’ with current technology, so they need to continue finding evidence of their influence on what we do know exists in the edges of our Solar System.

photo credit: Lexicon via wikimedia commons. The most distant of these outer solar system objects share a trait that hints at an unknown planet.

The possibility of a planet lurking in the outer reaches of the solar system has gained new ground, based on the orbits of recently discovered objects. There is a new twist to the latest evidence, however, with suggestions of not one but two large planets at mind-bending distances from the Sun.

The quest for a "Planet X" beyond Neptune has been going on for more than a century. Recently, two dwarf planets Senda and 2102 VP113 have been identified with orbits extending to distances hundreds of times further from the Sun than our own.

Instead it is thought that these objects formed closer to the sun. The gravitational influence of a large planet is one explanation of how their orbits changed. The theory has its own problems – if we can’t explain how objects like these came to be orbiting at such distances, then it’s equally unclear how a theoretical planet came to be there.

Yet all of these distant objects reach their closest point to the sun just when they are near the plane the planets circle in. The scientists considered this unlikely to be a coincidence, and speculate it might be a sign of a planet influencing all of their orbits.

E. Otwell. The two most distant minor planets have very different orbits, but converge when closest to the sun.

In Monthly Notices of the Royal Astronomical Society Letters brothers Carlos and Raul de la Fuente Marcos of Complutense University of Madrid have taken this a step further. “The analysis of several possible scenarios strongly suggest that at least two trans-Plutonian planets must exist,” they conclude.

Even more recently, Lorenzo Iorio of the Italian Ministry of Education, Universities and Research has argued in the same journal that if planet X exists, it must be much further out than Trujillo and Sheppard proposed. How far it would need to be depends on its mass, but an unknown object twice as heavy as the Earth could not be less than 500 AU from the Sun, Iorio maintains.

Other astronomers are more cautious. David Jewitt of the University of California, Los Angeles told Science News, "The outer solar system can be full of all sorts of unseen and interesting things,” Jewitt says, “but the argument ... for a massive perturber is a bit puzzling.” Jewitt notes that if the Kuiper Belt Objects in the Trujillo/Sheppard study have a planet keeping them in line, it may well be Neptune. Sedna and 2012 VP113 are too far out for this to be true for them as well, but it is far easier to explain two orbits as coincidences than twelve.

While the question may only be finally settled by the discovery of a large planet lurking in space, a number of teams have redoubled their efforts to find modest sized objects whose orbits might help us lend credence to, or reject, the theories proposed so far.

An incredible video posted to YouTube on Oct. 25, shows what looks unmistakably like the giant Sphinx in Egypt, but on the surface of Mars. The similarity to the ancient structure on Earth is undeniable, and straight lines cut into its base don't look like the byproduct of simple erosion. The implication that an ancient civilization once thrived on Mars is inescapable, after closer scrutiny of this unusual find.

Paranormal Crucible @YouTube

The video, posted by intrepid alien hunter Paranormal Crucible, a YouTube channel known for digging up all kinds of oddities on the Red Planet, zooms in on the statue and enhances the image with some simple coloring techniques. Otherwise, the photo, taken by the Mars Curiosity rover and posted to NASA's public website, speaks for itself, with a startling likeness to ancient structures made by humans on Earth in the distant past.

The conclusion that this "Sphinx" lookalike is the work of an ancient race, which sprang up from Mars before the planet's atmosphere became hostile to life, or is the work of visiting aliens, who left the statue behind as a relic before inspiring similar carvings on Earth thousands of years ago, is hard to refute.

Facts which support such a seemingly outlandish conclusion apply to this latest Mars anomaly, even more so than any other, because of the obviously intelligent design and carefully crafted foundation of the statue. Consisting of ramrod straight parallel lines, carved in the shape of steps, the pedestal of the Sphinx causes one to question whether the normal erosion on the hostile surface of Mars could be responsible for such an anomaly.

Straight lines in rock strata are rare, even on Earth, and usually indicate conscious intention on the part of the carver. The explanation that these lines, dramatically pointing up the "head" of the monument, are merely the result of coincidence, no matter how similar to man made objects, is stretched to the breaking point now that this unusual structure has been found.

Exploring the possibility is, of course, rather limited, as the Curiosity rover is intended to investigate whether microbial life still exists on Mars, and these photo anomalies are not the primary focus. But, that could change, and quickly, now that legendary astronaut, and the second man to walk on the Moon, Buzz Aldrin, is calling for humans to travel to and colonize Mars in the near future.

Perhaps if an astronaut can get close enough to this, and other Martian anomalies, the question can be settled once and for all as to whether or not an ancient civilization once lived, and died, on Mars, the closest planetary neighbor to Earth.

What do you think? Have a look at the video above, and please feel free to leave a comment below. Is this evidence of alien life on the Red Planet? Can this object really be an ancient Sphinx carved out of the rocky surface of Mars?